Night vision systems generally operate in the near infrared (IR) illumination range employing artificial illumination source(s) to illuminate a field of view. It has been proposed to employ night vision systems on automotive systems that illuminate the road scene in front of the vehicle with infrared radiation. The infrared illumination may illuminate a field of view well beyond the visible light illumination achieved with conventional vehicle headlights, without blinding passengers in oncoming traffic.
In conventional infrared light illumination systems, large power-consuming and inefficient illumination sources are typically employed to provide sufficient illumination for imaging devices to capture the forward road scene. The conventional illumination source typically includes a filament lamp which requires several hundred watts of power to provide the necessary illumination to cover a desired field of view with a range that extends up to one hundred fifty meters (150 m). Typically, expensive thermal management techniques are generally needed to ensure proper operation of the illumination sources in conventional illuminator assemblies.
In many night vision systems, only the infrared portion of the electromagnetic energy spectrum is used for the illumination of a desired field of view. The energy outside of the infrared spectrum, including the visible light energy, is generally discarded. Additionally, many night vision systems generally employ thermal energy management techniques, which add size and expense to the overall illuminator package. Thus, conventional night vision illuminators are generally energy inefficient and costly.
It is therefore desirable to provide for an infrared illuminator that is energy efficient and cost affordable. In particular, it is desirable to provide for an infrared illuminator that efficiently illuminates infrared radiation from a vehicle to enable night vision.